#!/usr/bin/env python3
# -*- coding: utf-8 -*-

import sys


def test():
    args = sys.argv
    if len(args) == 1:
        print("Hello world!")
    elif len(args) == 2:
        print(f"Hello {args[1]}")
    else:
        print("too many arguments")


if __name__  == "__main__":
    test()
